German OS 37 15 831 shows a vacuum coating system for vapor deposition of anti-reflection coating layers on optical substrates such as lenses for plastic eyeglasses. The lenses can be clamped on a carrier that rotates in an evacuatable chamber above a vaporization source. The carrier is formed by a plurality of planar carrier plates which are arranged and supported to approximate a portion of a sphere, each of which is capable of at least 180.degree. of rotation relative to the other plates. Every carrier plate includes a plurality of openings in which are mounted substrate holders including at least one retaining spring. The substrate holders are freely tiltable, from both sides, out of the plane of the carrier plate up to a predetermined angle. Thus, every substrate holder includes a resilient and freely tiltable mount secured to the carrier plate.
European Patent No. 215 261 teaches a lens holder for eyeglass lenses to be cleaned and subsequently coated. The lens holder is fashioned as a ring having an interior surface from which extends a plurality of notched projections which accept the lenses to be held. The ring is elastically deformable, and the notched projections are arranged generally opposite one another.